1. Field of the Invention
This invention relates to a method of evaluating the cooling performance of a heat treatment agent and an apparatus therefor.
2. Description of the Prior Art
When articles to be treated such as metallic parts are hardened by use of a heat treatment agent such as a quenching oil, occurrences of hardening strains and quench irregularities depend on the cooling performance of the heat treatment agent. However, in addition thereto there are other major influences exerted by factors other than the cooling performance itself, such as a construction of a treatment tank including an oil tank and the like, positions and conditions of arrangement of the articles in the treatment tank, further, uniformity or nonuniformity of the fluidized conditions of the heat treatment agent in the treatment tank, nonuniformity in the distribution of temperature adjacent the articles due to the nonuniformity of the heat treatment agent, and the like. However, in the case of evaluating the cooling performance of a heat treatment agent in the past, only the heat treatment agent has been subjected to a sampling test for the evaluation of the cooling performance thereof, with the above-mentioned various factors being unable to be taken into consideration as according to K 2242 Method of Japanese Industrial Standard (JIS). Furthermore, there have been cases where trial quenches have been performed to judge the cooling performance from the results thus obtained. However, it has been impossible to obtain the objective and quantitative results in such cases as described above.